89955-34-0Relevant academic research and scientific papers
Ligand steric effects on the photophysics of bis- and tris(2,2′-bipyridine) complexes of rhodium(III)
Nishizawa,Suzuki,Sprouse,Watts,Ford
, p. 1837 - 1841 (2008/10/08)
The effects of 3,3′-dimethyl steric interactions on the luminescence of 2,2′-bipyridine complexes of rhodium(III) have been investigated. The tris complex, Rh(dmbpy)33+, is found is display both metal-centered and ligand-centered emissions. The metal-centered emission is the dominant luminescence feature at 77 K, but the ligand-centered emission is enhanced relative to the metal-centered luminescence in fluid solutions. The bis complex, Rh(dmbpy)2Cl2+, displays a dominant ligand field emission under all conditions that were studied. Reinvestigation of the luminescence of the tris(1,10-phenanthroline) and tris(2,2′-bipyridine) complexes of Rh(III) in fluid solutions indicates that these species emit only from ligand-centered excited states. Comparison of the 3,3′-dimethyl-2,2′-bipyridine and unsubstituted 2,2′-bipyridine complexes of Rh(III) indicates that both ligand-centered and metal-centered excited states have lower energies for the methyl-substituted complexes but the effect is larger for the metal-centered states.
